refactor: remove 17-byte FFE4 and 33-byte FFE1 legacy compat code

- Remove parseVendorStatus 17-byte branch (FFE4 is now 19 bytes)
- Remove parseVendorStatus 33-byte branch (FFE1 is now 34 bytes)
- Remove buildVendorCommand33 deprecated alias
- Remove fitting/run_state !== -1 guards in connection.js
- Update commands.js to use buildVendorCommand directly

miniprogram/services/ble/connection.js

@@ -101,12 +101,8 @@ function handleValueChange(res) {
       }
       emit('adc', { pd: parsed.pd, vbat: vbatMv, battery: batteryPct, fitting: parsed.fitting, run_state: parsed.run_state })
       emit('battery', { battery: batteryPct, vbat: vbatMv })
-      if (parsed.fitting !== -1) {
-        emit('fitting', { fitting: parsed.fitting })
-      }
-      if (parsed.run_state !== -1) {
-        emit('run_state', { run_state: parsed.run_state })
-      }
+      emit('fitting', { fitting: parsed.fitting })
+      emit('run_state', { run_state: parsed.run_state })
       return
     }